Fabric column and pad concrete form

ABSTRACT

A lightweight and flexible concrete forming tube for columns and pads is disclosed, wherein the tube has a very thin wall of high strength fabric and a longitudinal fabric tab running the length of the tube. The tab is sandwiched between two vertical support members made of lumber. The vertical support members and attached fabric tube are then accurately located and braced. As the interior of the tube is filled with concrete, the hydrostatic pressure causes the tube to form a cylindrical shape, thereby accurately aligning itself across from the vertical support members. The use of fabric prevents the problems associated with using cardboard forms, which weaken when exposed to moisture.

[0001] This invention provides a means of forming a concrete column andfooting at the same time.

METHOD CURRENTLY BEING USED, PROBLEMS WITH METHOD

[0002] Steel piers and concrete footings are currently being used tosupport modular and HUD code buildings as shown in FIG. 1. The pier issuspended from the bottom of the building with the pier's base aboutthree inches off the ground. A fabric bag, with an opening on the top,and a tie string around the opening, is tied tight around the base ofthe steel pier. Concrete is pumped into the bag, encapsulating the baseof the pier to form a concrete footing.

[0003] The problem is that various heights must be accommodated in thefield, and this necessitates keeping a large inventory of steel pierswith different heights, usually with 2″ height increments.

DESCRIPTION OF THE INVENTION

[0004] This invention proposes to extend the top of the footing bag witha fabric tube. With this method, the number of different sized steelpiers can be reduced significantly; and in one embodiment of theinvention, the steel pier is eliminated.

EMBODIMENTS OF THE INVENTION

[0005] 1. Using the Tube and Bag with a Steel Pier (FIG. 2)

[0006] With this embodiment, a fabric tube would be sewn to the openingof the forming bag. The diameter of the tube would be the same as thatof the opening in the bag. Along the top of this tube would be a secondtie cord. Hence either the lower cord or the upper cord could beattached to the base of the steel pier. The height of the tube could be(for example) about 6″, thereby eliminating three different heights ofsteel piers.

[0007] 2. Using the Tube and Bag under a Steel I-Beam without a SteelPier (FIG. 3)

[0008] This embodiment would consist of the following:

[0009] a. Fabric tube and bag, joined together to enable pouring of boththe footing and column at the same time;

[0010] b. A metal support assembly, which would hold the fabric tube ina vertical position at the correct height. This assembly would beattached to the building's I-beam. The fabric tube would be sandwichedbetween a two-part sheet metal support assembly to hold the tubecorrectly.

[0011] c. Concrete would be pumped in the top of the tube, therebyfilling the footing bag first, and then the fabric tube. This wouldenable the load from the I-beam to be transferred to the ground below.

[0012] d. After several days, when the concrete has hardenedsufficiently, the installer would come back and use the adjustment nutto level up the I-beam.

[0013] 3. Using the Tube and Bag under a Rim Joist without a Steel Pierusing a Wood Support (FIG. 3)

[0014] This embodiment would consist of the following:

[0015] a. Fabric tube and bag, joined together to enable pouring of boththe footing and column at the same time. The fabric tube would have afabric tab several inches in width, running continuously the tube's fullheight (for stapling to the wooden support member);

[0016] b. A temporary support member (perhaps made of wood) screwed tothe rim joist, and extending vertically downwards to the top of thefooting form.

[0017] c. The tube tab would be stapled in position to the side of thetemporary wooden support member so that the tube and footing form isheld in correct position. It may be necessary to attach a second woodsupport adjacent to the first to prevent the tube from swinginghorizontally;

[0018] d. Using a small grout pump, concrete would be pumped into thetop of the fabric tube, up to the bottom of the rim joist so that theloads from the floor system will be transferred to the concrete, down tothe ground below.

[0019] e. The next day or so, the temporary supports would be removed toenable the installation of skirting adjacent to the concrete columns.

[0020] 4. Using the Tube and Bag under a Rim Joist without a Steel Pierusing a Steel Support

[0021] This embodiment would consist of the following (see FIG. 4):

[0022] a. Fabric tube and bag, joined together to enable pouring of boththe footing and column at the same time;

[0023] b. A support member made of sheet metal is screwed to the rimjoist, and extending vertically downwards. This member could incorporatean anchor entering the concrete to tie the building to the concretecolumn.

[0024] c. The fabric tube would be cut to the correct length, and slidover the support member. A cap would then be attached to the supportmember, sandwiching the fabric tube between the two in the correctposition. The support member could also assist in transferring the floorloads to the concrete column, as well as reinforce the concrete;

[0025] d. Using a small grout pump, concrete would be pumped into thetop of the fabric tube, right up to the bottom of the rim joist so thatthe loads from the floor system are transferred to the concrete, down tothe ground below

[0026] e. Following the concrete pour, skirting would then be affixed tothe outside of the concrete columns.

What is claimed is:
 1. A prefabricated column or pad tube formcomprising: a. At least one flexible sheet form element of indefinitelength and specified width such that one longitudinal edge is joined toeither: i. The opposing longitudinal edge, at a specific distance fromthe edge to create a flexible tube form element of indefinite length,specific diameter, and a longitudinal tab adjacent to the joining width;ii. The adjacent longitudinal edge of a separate flexible sheet formelement, at a specific distance from its edge to create at least aportion of a flexible tube form element of indefinite length, andlongitudinal tab adjacent to the joining width of indefinite length, sothat the multiplicity of joined flexible sheet form elements forms aspecific diameter tube with a multiplicity of longitudinal tabs adjacentto each joining width.
 2. The prefabricated column or pad tube form asclaimed in claim 1, in which the flexible sheet form element is made ofa woven fabric.
 3. The prefabricated column or pad tube form as claimedin claim 2, in which the woven fabric is of such a nature that itadheres to the hardened concrete, and cannot be stripped.
 4. Theprefabricated column or pad tube form as claimed in claim 3, in whichthe woven fabric contains certain high strength warp and or weftelements to add structural strength to the concrete column or pad. 5.The prefabricated column or pad tube form as claimed in claim 1, inwhich the longitudinal edges of at least two adjacent flexible sheetform elements are longitudinally joined temporarily by a zipper or othertemporary forming method.
 6. A method of constructing a concrete columncomprising the steps of: a. Cutting off a specified length of at leastone flexible sheet form element and at least one longitudinal tab joinedinto a tube form element of specified diameter, with the specifiedlength equal to the height of the desired concrete column; b.Sandwiching the longitudinal tabs between pairs of vertical supportmembers; c. Positioning and bracing the vertical support members aroundthe circumference of the proposed column; d. Supplying a flowable andsettable foundation material to substantially fill the space within theflexible tube element.
 7. A method of constructing a concrete column asclaimed in claim 6 in which the flexible tube form element is left inplace on the concrete surface.
 8. A method of constructing a concretepad comprising the steps of: a. Cutting off a specified length of atleast one flexible sheet form element and at least one longitudinal tabjoined into a tube form element, of specified diameter and specifiedlength equal to the height of the desired concrete pad; b. Drivingstakes around the perimeter at the location of the desired pad, thespacing of the stakes equal to the spacing of the longitudinal tabsaround the perimeter of the tube form element; c. Attaching thelongitudinal tabs to the stakes; d. Supplying a flowable and settablefoundation material to substantially fill the space within the flexibletube form element.